Skip to content

Commit

Permalink
Update CmcdDataBuilder's code after review
Browse files Browse the repository at this point in the history
  • Loading branch information
@peaBerberian
peaBerberian committed Jun 25, 2024
1 parent 2be6c9b commit 73828f9
Show file tree
Hide file tree
Showing 2 changed files with 137 additions and 142 deletions.
16 changes: 8 additions & 8 deletions doc/api/Miscellaneous/plugins.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -145,10 +145,10 @@ As you can see, this function takes two arguments:
When `type` is set to `"query"`, then `value` represents a CMCD payload formatted to
be inserted in a query string. It is in this case an array of 2-tuples with the first
value being a field's name as a string and the second element being either that
field's value if set to a string or indicating that the field has no value.
For example a `value` set to `[["first", "val"], ["second", null],
["third", "something"]]` could be translated into the query string
`?first=val&second&third=something`.
field's value if set to a string or indicating that the field has no value. For
example a `value` set to
`[["first", "val"], ["second", null], ["third", "something"]]` could be translated
into the query string `?first=val&second&third=something`.

When `type` is set to `"headers"`, then `value` represents a CMCD payload formatted
to be inserted as headers. It is in this case an object where keys are header names
Expand Down Expand Up @@ -315,10 +315,10 @@ As you can see, this function takes three arguments:
When `type` is set to `"query"`, then `value` represents a CMCD payload formatted to
be inserted in a query string. It is in this case an array of 2-tuples with the first
value being a field's name as a string and the second element being either that
field's value if set to a string or indicating that the field has no value.
For example a `value` set to `[["first", "val"], ["second", null],
["third", "something"]]` could be translated into the query string
`?first=val&second&third=something`.
field's value if set to a string or indicating that the field has no value. For
example a `value` set to
`[["first", "val"], ["second", null], ["third", "something"]]` could be translated
into the query string `?first=val&second&third=something`.

When `type` is set to `"headers"`, then `value` represents a CMCD payload formatted
to be inserted as headers. It is in this case an object where keys are header names
Expand Down
263 changes: 129 additions & 134 deletions src/core/cmcd/cmcd_data_builder.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,6 +89,11 @@ export default class CmcdDataBuilder {
private _bufferStarvationToggle: boolean;
private _canceller: TaskCanceller | null;

/**
* Create a new `CmcdDataBuilder`, linked to the given options (see type
* definition).
* @param {Object} options
*/
constructor(options: ICmcdOptions) {
this._sessionId = options.sessionId ?? createUuid();
this._contentId = options.contentId ?? createUuid();
Expand All @@ -102,6 +107,16 @@ export default class CmcdDataBuilder {
this._canceller = null;
}

/**
* Start listening to the given `playbackObserver` so the `CmcdDataBuilder`
* can extract some playback-linked metadata that it needs.
*
* It will keep listening for media data until `stopMonitoringPlayback` is called.
*
* If `startMonitoringPlayback` is called again, the previous monitoring is
* also cancelled.
* @param {Object} playbackObserver
*/
public startMonitoringPlayback(
playbackObserver: IReadOnlyPlaybackObserver<ICmcdDataBuilderPlaybackObservation>,
): void {
Expand All @@ -118,16 +133,33 @@ export default class CmcdDataBuilder {
);
}

/**
* Stop the monitoring of playback conditions started from the last
* `stopMonitoringPlayback` call.
*/
public stopMonitoringPlayback(): void {
this._canceller?.cancel();
this._canceller = null;
this._playbackObserver = null;
}

/**
* Update the last measured throughput for a specific media type.
* Needed for some of CMCD's properties.
* @param {string} trackType
* @param {number|undefined} throughput - Last throughput measured for that
* media type. `undefined` if unknown.
*/
public updateThroughput(trackType: ITrackType, throughput: number | undefined) {
this._lastThroughput[trackType] = throughput;
}

/**
* Returns the base of data that is common to all resources' requests.
* @param {number|undefined} lastThroughput - The last measured throughput to
* provide. `undefined` to provide no throughput.
* @returns {Object}
*/
private _getCommonCmcdData(lastThroughput: number | undefined): ICmcdProperties {
const props: ICmcdProperties = {};
props.bs = this._bufferStarvationToggle;
Expand All @@ -151,6 +183,12 @@ export default class CmcdDataBuilder {
return props;
}

/**
* For the given type of Manifest, returns the corresponding CMCD payload
* that should be provided alongside its request.
* @param {string} transportType
* @returns {Object}
*/
public getCmcdDataForManifest(transportType: string): ICmcdPayload {
const props = this._getCommonCmcdData(
this._lastThroughput.video ?? this._lastThroughput.audio,
Expand All @@ -171,6 +209,12 @@ export default class CmcdDataBuilder {
return this._producePayload(props);
}

/**
* For the given segment information, returns the corresponding CMCD payload
* that should be provided alongside its request.
* @param {Object} content
* @returns {Object}
*/
public getCmcdDataForSegmentRequest(content: ICmcdSegmentInfo): ICmcdPayload {
const lastObservation = this._playbackObserver?.getReference().getValue();

Expand Down Expand Up @@ -266,156 +310,111 @@ export default class CmcdDataBuilder {
return this._producePayload(props);
}

/**
* From the given CMCD properties, produce the corresponding payload according
* to current settings.
* @param {Object} props
* @returns {Object}
*/
private _producePayload(props: ICmcdProperties): ICmcdPayload {
let cmcdObjectValue = "";
let cmcdRequestValue = "";
let cmcdSessionValue = "";
let cmcdStatusValue = "";
const headers = {
object: "",
request: "",
session: "",
status: "",
};
let queryStringPayload = "";
if (props.br !== undefined) {
queryStringPayload += `br=${String(props.br)},`;
const toAdd = `br=${String(props.br)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdObjectValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.bl !== undefined) {
const toAdd = `bl=${String(props.bl)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdRequestValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.bs === true) {
const toAdd = "bs,";
if (this._typePreference === TypePreference.Headers) {
cmcdStatusValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.cid !== undefined) {
const toAdd = `cid=${formatStringPayload(props.cid)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdSessionValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.d !== undefined) {
const toAdd = `d=${String(props.d)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdObjectValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.dl !== undefined) {
const toAdd = `dl=${String(props.dl)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdRequestValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.mtp !== undefined) {
const toAdd = `mtp=${String(props.mtp)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdRequestValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.ot !== undefined) {
const toAdd = `ot=${props.ot},`;
if (this._typePreference === TypePreference.Headers) {
cmcdObjectValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.pr !== undefined) {
const toAdd = `pr=${String(props.pr)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdSessionValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.rtp !== undefined) {
const toAdd = `rtp=${String(props.rtp)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdStatusValue += toAdd;
} else {
queryStringPayload += toAdd;
}
}
if (props.sf !== undefined) {
const toAdd = `sf=${props.sf},`;

const addPayload = (payload: string, headerName: keyof typeof headers): void => {
if (this._typePreference === TypePreference.Headers) {
cmcdSessionValue += toAdd;
headers[headerName] += payload;
} else {
queryStringPayload += toAdd;
queryStringPayload += payload;
}
}
if (props.sid !== undefined) {
const toAdd = `sid=${formatStringPayload(props.sid)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdSessionValue += toAdd;
} else {
queryStringPayload += toAdd;
};

const addNumberProperty = (
prop: "br" | "bl" | "d" | "dl" | "mtp" | "pr" | "rtp" | "tb",
headerName: keyof typeof headers,
): void => {
const val = props[prop];
if (val !== undefined) {
const toAdd = `${prop}=${String(val)},`;
addPayload(toAdd, headerName);
}
}
if (props.st !== undefined) {
const toAdd = `st=${props.st},`;
if (this._typePreference === TypePreference.Headers) {
cmcdSessionValue += toAdd;
} else {
queryStringPayload += toAdd;
};

const addBooleanProperty = (
prop: "bs" | "su",
headerName: keyof typeof headers,
): void => {
if (props[prop] === true) {
const toAdd = `${prop},`;
addPayload(toAdd, headerName);
}
}
if (props.su === true) {
const toAdd = "su,";
if (this._typePreference === TypePreference.Headers) {
cmcdRequestValue += toAdd;
} else {
queryStringPayload += toAdd;
};

const addStringProperty = (
prop: "cid" | "sid",
headerName: keyof typeof headers,
): void => {
const val = props[prop];
if (val !== undefined) {
const formatted = `"${val.replace("\\", "\\\\").replace('"', '\\"')}"`;
const toAdd = `prop=${formatted},`;
addPayload(toAdd, headerName);
}
}
if (props.tb !== undefined) {
const toAdd = `tb=${String(props.tb)},`;
if (this._typePreference === TypePreference.Headers) {
cmcdObjectValue += toAdd;
} else {
queryStringPayload += toAdd;
};

const addTokenProperty = (
prop: "ot" | "sf" | "st",
headerName: keyof typeof headers,
): void => {
const val = props[prop];
if (val !== undefined) {
const toAdd = `prop=${val},`;
addPayload(toAdd, headerName);
}
}
};

addNumberProperty("br", "object");
addNumberProperty("bl", "request");
addBooleanProperty("bs", "status");
addStringProperty("cid", "session");
addNumberProperty("d", "object");
addNumberProperty("dl", "request");
addNumberProperty("mtp", "request");
addTokenProperty("ot", "object");
addNumberProperty("pr", "session");
addNumberProperty("rtp", "status");
addTokenProperty("sf", "session");
addStringProperty("sid", "session");
addTokenProperty("st", "session");
addBooleanProperty("su", "request");
addNumberProperty("tb", "object");

if (this._typePreference === TypePreference.Headers) {
if (cmcdObjectValue[cmcdObjectValue.length - 1] === ",") {
cmcdObjectValue = cmcdObjectValue.substring(0, cmcdObjectValue.length - 1);
if (headers.object[headers.object.length - 1] === ",") {
headers.object = headers.object.substring(0, headers.object.length - 1);
}
if (cmcdRequestValue[cmcdRequestValue.length - 1] === ",") {
cmcdRequestValue = cmcdRequestValue.substring(0, cmcdRequestValue.length - 1);
if (headers.request[headers.request.length - 1] === ",") {
headers.request = headers.request.substring(0, headers.request.length - 1);
}
if (cmcdSessionValue[cmcdSessionValue.length - 1] === ",") {
cmcdSessionValue = cmcdSessionValue.substring(0, cmcdSessionValue.length - 1);
if (headers.session[headers.session.length - 1] === ",") {
headers.session = headers.session.substring(0, headers.session.length - 1);
}
if (cmcdStatusValue[cmcdStatusValue.length - 1] === ",") {
cmcdStatusValue = cmcdStatusValue.substring(0, cmcdStatusValue.length - 1);
if (headers.status[headers.status.length - 1] === ",") {
headers.status = headers.status.substring(0, headers.status.length - 1);
}
log.debug("CMCD: proposing headers payload");
return {
type: "headers",
value: {
/* eslint-disable @typescript-eslint/naming-convention */
"CMCD-Object": cmcdObjectValue,
"CMCD-Request": cmcdRequestValue,
"CMCD-Session": cmcdSessionValue,
"CMCD-Status": cmcdStatusValue,
"CMCD-Object": headers.object,
"CMCD-Request": headers.request,
"CMCD-Session": headers.session,
"CMCD-Status": headers.status,
/* eslint-enable @typescript-eslint/naming-convention */
},
};
Expand Down Expand Up @@ -596,7 +595,3 @@ interface ICmcdProperties {
*/
tb?: number | undefined;
}

function formatStringPayload(str: string): string {
return `"${str.replace("\\", "\\\\").replace('"', '\\"')}"`;
}

0 comments on commit 73828f9

Please sign in to comment.